Fabric sensing device

Abstract

A touch-sensitive textile device that is configured to detect the occurrence of a touch, the location of a touch, and/or the force of a touch on the touch-sensitive textile device. In some embodiments, the touch-sensitive textile device includes a first set of conductive threads oriented along a first direction, and a second set of conductive threads interwoven with the first set of conductive threads and oriented along a second direction. The device may also include a sensing circuit that is operatively coupled to the first and second set of conductive threads. The sensing circuit may be configured to apply a drive signal to the first and second set of conductive threads. The sensing circuit may also be configured to detect a touch or near touch based on a variation in an electrical measurement using the first or second set of conductive threads.

We claim: 
     
       1. A touch-sensitive textile device comprising:
 a first set of conductive threads oriented along a first direction; 
 a second set of conductive threads interwoven with the first set of conductive threads and oriented along a second direction; 
 a first group of nonconductive threads interwoven with the second set of conductive threads, wherein the first group of nonconductive threads is oriented along the first direction and forms a nonconductive strip region, wherein the first set of conductive threads includes a group of conductive threads forming a conductive strip region that is adjacent to the nonconductive strip region; 
 a second group of nonconductive threads interwoven with the first set of conductive threads oriented along the second direction; and 
 a sensing circuit operatively coupled to the first and second set of conductive threads, wherein the sensing circuit is configured to:
 apply a drive signal to the first and second set of conductive threads, and 
 monitor a collective charge on the group of conductive threads that form the conductive strip region to detect a variation in capacitive coupling with an object touching or nearly touching the touch-sensitive textile device. 
 
 
     
     
       2. The touch-sensitive textile device of  claim 1 , wherein sensing circuit is configured to detect a touch or near touch on the touch-sensitive textile based on a variation in the collective charge. 
     
     
       3. The touch-sensitive textile device of  claim 2 , wherein the sensing circuit is further configured to determine a location of the touch based on the variation in the collective charge. 
     
     
       4. The touch-sensitive textile device of  claim 1 , wherein the nonconductive strip region is one of a set of nonconductive strip regions, wherein the conductive strip region is one of a set of conductive strip regions, wherein the set of nonconductive strip regions and the set of conductive strip regions are arranged in an alternating pattern in both the first and second directions. 
     
     
       5. A touch-sensitive textile device comprising:
 a first set of conductive threads oriented along a first direction; 
 a second set of conductive threads interwoven with the first set of conductive threads and oriented along a second direction, wherein the second direction is orthogonal to the first direction; 
 a set of nonconductive threads interwoven with the first and second set of conductive threads, wherein each of the conductive threads in the first and second sets of conductive threads forms a stitch that passes over at least two adjacent nonconductive threads in the set of nonconductive threads; and 
 a sensing circuit operatively coupled to the first and second set of conductive threads, wherein the sensing circuit is configured to:
 apply a drive signal to the first set of conductive threads, 
 detect a variation in resistance between any one of the first set of conductive threads and any one of the second set of conductive threads, and 
 sense a touch on the first or second set of conductive threads based on the variation in resistance. 
 
 
     
     
       6. The touch-sensitive textile device of  claim 5 , wherein the sensing circuit is further configured to determine a location of the touch based on the variation in resistance. 
     
     
       7. A touch-sensitive textile device comprising:
 a first set of conductive threads disposed in a first textile layer; 
 a second set of conductive threads disposed in a second textile layer, wherein the first textile layer is formed from a first set of nonconductive threads interwoven with the first set of conductive threads and the second textile layer is formed from a second set of nonconductive threads interwoven with the second set of conductive threads; 
 a spacer structure separating the first and second textile layers, the spacer structure configured to deflect in response to a touch on the first or second textile layer; and 
 a sensing circuit operatively coupled to the first and second set of conductive threads, wherein the sensing circuit is configured to:
 apply a drive signal to the first set of conductive threads, and 
 detect a variation in resistance between any one of the first set of conductive threads and any one of the second set of conductive threads. 
 
 
     
     
       8. The touch-sensitive textile device of  claim 7 , wherein sensing circuit is configured to sense a touch on the first or second textile layers based on the variation in resistance. 
     
     
       9. The touch-sensitive textile device of  claim 8 , wherein the sensing circuit is further configured to determine a location of the touch based on the variation in resistance. 
     
     
       10. The touch-sensitive textile device of  claim 7 , wherein the spacer structure is a monofilament yarn interwoven between the first and second textile layers. 
     
     
       11. A touch-sensitive textile device comprising:
 a first set of conductive threads disposed in a first textile layer; 
 a second set of conductive threads disposed in a second textile layer, wherein the first textile layer is formed from a first set of nonconductive threads interwoven with the first set of conductive threads and the second textile layer is formed from a second set of nonconductive threads interwoven with the second set of conductive threads; 
 a spacer structure separating the first and second textile layers, the spacer structure configured to deflect in response to a touch on the first or second textile layer; and 
 a sensing circuit operatively coupled to the first and second set of conductive threads, wherein the sensing circuit is configured to:
 apply a drive signal to the first set of conductive threads, and 
 detect a variation in capacitance between any one of the first set of conductive threads and any one of the second set of conductive threads due to a deflection in the spacer structure. 
 
 
     
     
       12. The touch-sensitive textile device of  claim 11 , wherein sensing circuit is configured to sense a touch on the first or second textile layers based on the variation in capacitance. 
     
     
       13. The touch-sensitive textile device of  claim 12 , wherein the sensing circuit is further configured to determine a location of the touch based on the variation in capacitance. 
     
     
       14. The touch-sensitive textile device of  claim 11 , wherein the spacer structure is a monofilament yarn interwoven between the first and second textile layers.